Abstract

King oyster mushroom with aroma has a commercial value in many countries worldwide. Due to increasing demands, researchers pay special attention to utilize suitable raw materials as media for growing this mushroom. This study, as a continuation of several studies, was conducted to identify further inputs for raising productivity of P. eryngii. The raw materials used were local recyclable residues including cardboard (C), spent coffee ground (SCG) and wheat straw (S) as substrates. The main culture was prepared using potato dextrose (PDA) and the spawns were propagated using rye grains. Four substrate formulations (F) were composed for the formation of basidiocarp: viz., F1 (100% S); F2 (50% S + 50% C); F3 (70% S + 30% C), and F4 (50% S + 50% SCG). Duration for spawn run and pinhead formation was recorded. The mean values of the shortest period for running spawn and pinhead initiation were in the substrate formulation F2 (33 and 47 days, respectively), while the longest period was in the substrate F4 with 62 and 78 days, respectively. The mushroom was harvested at the earliest in 60 days in F2, while it took 67 days in the substrate formulation F3 and 71 days in F1. The highest yield per 500g of the substrate (with 65% moisture) was 131 g in F2 (50% S + 50% C) while no oyster mushroom yield was not produced in the substrate F4 with 50% S+50% SCG. The results showed that 50% wheat straw + 50% cardboard mixture was by far superior to the other formulations tested. Spent coffee ground failed to support the growth and yield of king oyster mushroom (Pleurotus eryngii).